The purpose of this project is to study the kidney, the small blood vessels and the lung in various diseases by means of special light microscopy techniques, immunofluorescence microscopy, electron microscopy and histochemical methods, and to correlate the structural variations with physiological parameters and with clinical behavior. Encompassed in the study will be the intrinsic renal diseases such as glomerulonephritis, systemic diseases, particularly diseases of connective tissue which involve the kidney and small blood vessels; various diseases of the lung affecting the alveolar septa and their capillaries; pulmonary and pleural tumor associated with environmental exposure; and renal, pulmonary and vascular abnormalities induced by various means in experimental animals. Extensive use of biopsy material, primarily that of the kidney, but also of the lung and connective tissue will permit simultaneous evaluations of structure and function and will also allow to follow the development of the disease from its inception to resolution or to a fatal outcome. Study of biopsies will be supplemented by autopsy material wherever this will be available. The main objective of this particular period of research will be longitudinal studies of renal biopsy material and correlation with long term follow-up of the patients. It is hoped to develop a better understanding of the nature of diseases involving the kidney, the small blood vessels and the connective tissue, to establish the natural course of these diseases and the effect of various modes of therapy. Because of the unexpected and untimely death of Dr. Nicholas Gang, a number of chemical studies that were started during the current grant period are not included in this proposal. These studies will be resumed as soon as a highly qualified replacement for Dr. Gang is found.